Fuel Tank

ABSTRACT

A fuel tank for a fuel-operated down-the-hole drill including a drill bit, is provided. A largest rotation diameter of the fuel tank is provided at or in connection with drilling equipment and is sufficiently small in order to be able to insert the fuel tank into a drill hole.

BACKGROUND

The invention relates to a fuel tank for a fuel-operated down-the-hole drill comprising a drill bit.

Furthermore, the invention relates to a method for feeding a fuel-operated down-the-hole drill comprising a drill bit with fuel.

The invention also relates to an arrangement for feeding a fuel-operated down-the-hole drill comprising a drill bit with fuel, the arrangement comprising a down-the-hole drill and a fuel tank as well as means for feeding fuel from the fuel tank to the down-the-hole drill.

The invention also relates to a rock drilling rig.

Holes can be drilled in rock by means of various rock drilling machines. Drilling may be performed with a method combining percussions and rotation (percussive drilling), or drilling may be based on mere rotation without a percussive function (rotary drilling). Further, percussive drilling may be classified according to whether the percussion, device is outside the drill hole or in the drill hole during the drilling. When the percussion device is outside the drill hole, the drilling is usually called top hammer drilling, wherein so-called top hammers are used, and when the percussion device is in the drill hole, the drilling is typically called down-the-hole drilling (DTH) and the drilling machine may be called a DTH drill or down-the-hole drill, for example.

In connection with fuel-operated down-the-hole drills, fuel feeding generally causes various problems. Fuel feeding from a fuel tank to the drill is typically arranged by means of fuel feed hoses or other corresponding feed lines, which take up space and may become damaged under difficult operating conditions.

BRIEF DESCRIPTION

The object of the invention is to provide a new and improved fuel tank, rock drilling rig and apparatus and method for feeding a fuel-operated rock drill with fuel. The object of the invention is achieved by an apparatus, arrangement and method that are characterised by what is defined in the independent claims. Some preferred embodiments of the invention are disclosed in the dependent claims.

According to an aspect of the invention, the largest rotation diameter of the fuel tank in the transverse direction of the drill hole is at the most equal to the largest rotation diameter of the drill bit, whereby the fuel tank may be inserted into the drill hole and the fuel tank is provided at the drilling equipment or in connection with it.

The idea of the present solution is that the fuel tank of the down-the-hole drill is formed in such a manner that it may be inserted into the drill hole together with the down-the-hole drill.

The present solution provides the advantage that, in fuel feeding of a fuel-operated down-the-hole drill, it is possible to avoid fuel feeding to the down-the-hole drill in the drill hole from outside the drill hole, which is laborious and susceptible to damage. By positioning the fuel tank in proximity to the down-the-hole drill, problems connected with long fuel feed hoses and the positioning thereof, for instance, can be avoided.

The idea of an embodiment is that the fuel tank is provided at the drill rod or in connection with it.

The idea of a second embodiment is that the fuel tank is provided at the down-the-hole drill or in connection with it.

The idea of a third embodiment is that the fuel tank is provided with means for pressurizing the fuel tank.

The idea of a fourth embodiment is that the means for pressurizing the fuel tank comprise a flushing air channel.

The idea of a fifth embodiment is that the fuel tank is divided into at least a pressure space and a fuel space, which are separated from one another by an elastic, film-like material.

The idea of a sixth embodiment is that the volume of the fuel tank is such that it is possible to fit at least a fuel amount consumed by the down-the-hole drill during one work shift inside it.

The idea of a seventh embodiment is that a pressure is produced in the fuel tank by means of the flushing air channel.

The idea of an eighth embodiment is that pressure is produced in the fuel tank by pre-pressurizing the fuel tank during a fill-up of the tank.

The idea of a ninth embodiment is that the arrangement comprises at least one flushing air channel and that the flushing air channel is arranged to produce a pressure in the fuel tank.

The idea of a tenth embodiment is that the arrangement comprises a drill rod and that the fuel tank is arranged at the drill rod or in connection with it.

BRIEF DESCRIPTION OF THE FIGURES

Some embodiments will be explained in greater detail in the accompanying drawings, in which

FIG. 1 shows schematically a rock drilling machine,

FIG. 2 shows schematically a down-the-hole drill,

FIG. 3 shows schematically a drill hole in the direction of section A-A shown in FIG. 2,

FIGS. 4 a, 4 b, 4 c and 4 d show schematically some drill holes and embodiments of a fuel tank,

FIGS. 5 a and 5 b show schematically an embodiment of the fuel tank,

FIGS. 6 a and 6 b show schematically yet another embodiment of the fuel tank,

FIG. 7 shows schematically yet another embodiment of the fuel tank,

FIG. 8 shows schematically a flow chart of a method for feeding a down-the-hole drill with fuel,

FIG. 9 shows schematically an arrangement for feeding a fuel-operated down-the-hole drill with fuel, FIG. 10 shows schematically a second arrangement for feeding a fuel-operated down-the-hole drill with fuel, and

FIG. 11 shows schematically a third arrangement for feeding a fuel-operated down-the-hole drill with fuel.

In the figures, some embodiments of the present solution are shown in a simplified manner for the sake of clarity. Similar parts are marked with the same reference numbers in the figures.

DETAILED DESCRIPTION

FIG. 1 shows a rock drilling rig 1 that may comprise a movable carrier 2 provided with a drilling boom 3. The boom 3 is provided with a rock drilling unit 4 comprising a feed beam 5, a feed device 6 and a rotation unit 7. The rotation unit 7 may be supported to a carriage 8, or alternatively the rotation unit may comprise sliding parts or the like support members with which it is movably supported to the feed beam 5. The rotation unit 7 may be provided with drilling equipment 9 which may comprise one or more drilling tubes 10 connected to each other, and a drill bit 11 at the outermost end of the drilling equipment. The drilling unit 4 of FIG. 1 is intended for rotary drilling in which the rotation unit 7 is used for rotating the drilling equipment 9 around its longitudinal axis in direction R and, at the same time, the rotation unit 7 and the drilling equipment 9 connected to it are fed with feed force F by means of the feed device 6 in drilling direction B. Thus, the drill bit breaks rock due to the effect of rotation R and feed force F, and a drill hole 12 is formed. When the drill hole 12 has been drilled to a desired depth, the drilling equipment 9 can be pulled by means of the feed device 6 out of the drill hole 12 in return direction C, and the drilling equipment can be disassembled by unscrewing connection threads between the drilling tubes 10 by means of the rotation unit 7.

FIG. 2 shows a second drilling unit 4, which differs from the one in FIG. 1 in such a way that the drilling equipment 9 is provided with a percussion device 13. The percussion device 13 is thus at the opposite end of the drilling equipment 9 in relation to the rotation unit 7. During the drilling, the down-the-hole drill 13 is in the drill hole and the drill bit 11 may be connected directly to the down-the-hole drill 13.

FIG. 3 shows schematically a drill hole in the direction of section A-A shown in FIG. 2. Section A-A is also the transverse direction of the drill hole 12 and drilling direction. FIG. 3 thus shows the drill rod 10, the down-the-hole drill 13 and the drill bit 11 connected to one another from above.

FIGS. 4 a, 4 b, 4 c and 4 d show schematically different embodiments of a fuel tank. A fuel tank 17 is in this case dimensioned so that its external form and size are arranged to fit in the hole formed by the drill bit 11. Thus, the largest rotation diameter E of the fuel tank 17 in transverse direction A-A of the drill hole 12 is equal to or smaller than, i.e. at the most equal to, the largest rotation diameter D of the drill bit 11.

In this context, the largest rotation diameter E, D of the fuel tank 17 and the drill bit 11 refers to the diameter of the circle that is formed by the most distant point from the rotation centre point G of the transverse A-A cross section of the fuel tank 17 or the drill bit 11 when said cross section is turned with respect to the drilling axis H extending in drilling direction B-C and passing through the rotation centre point G. The largest rotation diameter E is thus twice as large in length as the distance between said most distant point of the cross section of the fuel tank 17 or the drill bit 11 and said rotation centre point G. Consequently, the fuel tank 17 has thus enough space to turn around the drilling axis H in the drill hole formed by the drill bit 11. The most distant point of the cross section of the drill bit 11 from the rotation centre point G may be, for instance, the tip of the cutting edge or edges of the drill bit 11, not shown in the figures, in which case the largest rotation diameter D may be the diameter of a circle drawn in transverse direction A-A around the tips of the cutting edges of the drill bit 11.

The figures only show some examples for illustrating the largest rotation diameter E of a fuel tank, and in different embodiments the cross section of the fuel tank may differ considerably from what is described herein.

When the rotation diameter E of the fuel tank 17 is dimensioned to be equal to or smaller than the largest rotation diameter D of the drill bit, the fuel tank 17 may preferably be arranged at the drilling equipment 9 or in connection with it, for instance in connection with the down-the-hole drill 13 and/or the drill rod 10, and inserted into the drill hole 12. Thus, it is possible to avoid the feeding of fuel to the fuel tank 17 from outside the drill hole by using unhandy fuel hoses susceptible to damage.

FIGS. 5 a and 5 b show schematically an embodiment of the fuel tank 17, wherein the fuel tank 17 is arranged in connection with the drill rod 10, or more specifically, inside the drill rod 10. In FIG. 5 a, the embodiment is shown in partial side section and, in FIG. 5 b, in partial cross section. In this embodiment, not only the fuel tank but also a flushing air channel 18, such as a flushing air hose or tube, is arranged inside the drill rod 10. FIGS. 4 a, 4 b, 4 c and 4 c do not show the flushing air channel 18, but in different embodiments the flushing air channel 18 may be arranged, for example, to extend through the fuel tank 17 or, for example, to the edges of the fuel tank 17 in grooves 27 arranged for this purpose, as shown in FIG. 4 d, for example.

FIGS. 6 a and 6 b show schematically an embodiment of the fuel tank 17, wherein the cross section of the fuel tank 17 is substantially circular and the drill rod 10 is arranged in a tubular hole formed in the middle of the fuel tank. In FIG. 6 a, the embodiment is shown in partial side section and, in FIG. 6 b, in partial cross section. In FIGS. 6 a and 6 b, the cross section of the fuel tank 17 is substantially round, but different embodiments may also introduce other types of cross sections, as long as the largest rotation diameter E of the fuel tank is equal to or smaller than the largest rotation diameter D of the drill bit and the fuel tank 17 is arranged with respect to the drill rod 10 and the down-the-hole drill 13 in such a manner that it has enough space to be lowered into the drill hole 12. A feasible flushing air channel 18 marked with a dash line in FIGS. 6 a and 6 b may be arranged to extend inside the drill rod 10.

FIG. 7 shows yet another embodiment of the fuel tank 17, wherein the fuel tank is substantially tubular, for instance cylindrical, and arranged between the drill rod 10 and the down-the-hole drill 13 and the flushing air channel 18 is arranged to extend through the fuel tank.

FIG. 8 shows schematically a method for feeding a fuel-operated down-the-hole drill with fuel. The present method comprises inserting 801 the down-the-hole drill 13 and preferably the fuel tank 17, which is preferably arranged at the drilling equipment 9 or in connection with it and the largest rotation diameter E of which in transverse direction A-A of the drill hole is equal to or smaller than the largest rotation diameter D of the drill bit 11, into the drill hole 12, producing 802 a pressure in the fuel tank 17 for improving the fuel feeding, and feeding 803 fuel from the fuel tank 17 to the motor of the down-the-hole drill 13. The method may comprise an above-described fuel tank 17 and/or arrangement for feeding a fuel-operated down-the-hole drill comprising a drill bit 11 with fuel.

FIG. 9 shows schematically an arrangement for feeding a fuel-operated down-the-hole drill comprising a drill bit (11) with fuel. The arrangement may comprise a fuel tank 17, the rotation diameter E of which is equal to or smaller than the largest rotation diameter D of the drill bit 11, whereby the fuel tank 17 may be inserted into the drill hole 12, and which may be similar to one of the fuel tanks described above, for instance. The fuel tank 17 may comprise a feed port 23 for feeding fuel to the fuel tank 17 and a discharge port 24 for feeding fuel from the fuel tank 17 to the down-the-hole drill 13.

The fuel tank 17 may be pressurized in order to improve the fuel feeding by, for instance, dividing the fuel tank 17 into a pressure space 20 and a fuel space 21 by means of a film 19 to be arranged at the inner edges of the tank and made of an elastic film-like material, such as a rubber film, and providing the pressure space 20 with a pressure port 22 for supplying pressure to the fuel tank 17. In different embodiments, the fuel tank 17 may be pressurized by means of flushing air, for instance, such that the flushing air channel 18 is connected to the pressure port 22.

FIG. 10 shows schematically a second arrangement for feeding a fuel-operated down-the-hole drill comprising a drill bit 11 with fuel. The arrangement differs from the arrangement shown in FIG. 9 in that the fuel space 21 is separated from the pressure space 20 by means of an elastic film-like material, such as a rubber film, which forms a blister chamber 25 in the fuel tank 17 and the pressure space 20 inside it. In this case, pressure of the pressure space 20 is directed to the blister chamber 25 and the fuel in the fuel space 21 from every side. In other respects, the operation of the fuel tank may correspond to, for example, the fuel tanks 17 or the characteristics thereof described in connection with FIG. 9 and/or in connection with other present embodiments. The fuel tank 17 may be pressurized by, for instance, pre-pressurizing the pressure space 20 during a fuel fill-up and/or connecting the pressure space 20 to pressurizing means, such as the flushing air channel 18, of the fuel tank 17 via the pressure port 22.

FIG. 11 shows schematically a third arrangement for feeding a fuel-operated down-the-hole drill 13 comprising a drill bit 11 with fuel. The arrangement differs from the arrangements of FIGS. 9 and 10 in that, in the arrangement, a pressure is produced in the fuel space 21 by means of a ring-shaped piston 26. The ring-shaped piston 26 is moved by means of the pressure produced in the pressure space 20 towards the fuel space 21, i.e. downwards in FIG. 11, which increases the fuel pressure in the fuel space 21. Furthermore, unlike FIGS. 9 and 10, FIG. 11 shows a flushing air channel 18. The fuel tank 17 may be pressurized by, for instance, pre-pressurizing the pressure space 20 during a fuel fill-up and/or connecting the pressure space 20 to pressurizing means of the fuel tank via the pressure port 22. In an embodiment, the flushing air channel 18 may be connected to the pressure space in such a manner that the flushing air channel 18 may be used at least partly for pressurizing the fuel tank.

In different embodiments, the fuel tank 17 may preferably be arranged at the drilling equipment 9 or in connection with it, for instance in connection with the drill rod 10 and/or the down-the-hole drill 13, whereby the fuel tank 17 may be inserted into the drill hole 12 together with the drill rod 10 and the down-the-hole drill 13. In this case, the fuel tank 17 may be arranged, for instance, inside the drill rod 10, around the drill rod 10, or between the drill rod 10 and the down-the-hole drill 13. The volume of the fuel tank 1 is preferably dimensioned such that it is possible to fit at least a fuel amount consumed by the down-the-hole drill 13 during one work shift inside it. One work shift may last 8 to 10 hours, for example. To insert the fuel tank 17 into the drill hole 12, the largest rotation diameter E of the fuel tank 17 in transverse direction A-A of the drill hole must, however, be equal to or smaller than the largest rotation diameter D of the drill bit.

In different embodiments, the fuel tank 17 may be provided with means for pressurizing the fuel tank 17. By producing a pressure, for example at least 2 bar, in the fuel tank 17 by means of the arrangement described in connection with FIG. 9 or 10, for example, it is possible to direct a compression force to the fuel and thus to improve the fuel feeding to the down-the-hole drill 13 and its motor, in particular, and thus to optimize the volume of the fuel tank 17. By thus ensuring that substantially all of the fuel filled in the fuel tank 17 can be fed to the down-the-hole drill 13, it is, in other words, possible to minimize the size of the fuel tank 17.

When air or other suitable gas is used for flushing the drill hole, the flushing air channel 18 to be used for transferring the flushing air and the flushing air itself may be used for pressurizing the fuel tank, in other words, the means for pressurizing the fuel tank 17 may comprise the flushing air channel 18, for instance. In different embodiments, in addition to or instead of this, the fuel tank 17 may be pre-pressurized during a fill-up of the fuel tank 17, for instance, or a pressure may be produced in the fuel tank by other suitable method.

In different embodiments, the fuel may be liquid or gaseous. Furthermore, in different embodiments, the fuel tank 17 may be an easily detachable and mountable fuel module, which may also preferably be pre-pressurizable. Thus, the fuel tank can be replaced at the beginning or end of a work shift, for instance, and it can preferably be performed by means of conventional operational devices of the drilling equipment.

With the present solution, the fuel feeding of a fuel-operated down-the-hole drill 13 can thus be provided in such a manner that fuel need not be fed from outside the drill hole, and the fuel feeding does not require long fuel feed channels, which are often laborious to mount and possibly susceptible to damage.

In some cases, features disclosed in this application may be used as such, regardless of other features. On the other hand, when necessary, features disclosed in this application may be combined in order to provide various combinations.

The drawings and the related description are only intended to illustrate the idea of the invention. The details of the invention may vary within the scope of the claims. 

1. A fuel tank for a fuel-operated down-the-hole drill having a drill bit, the down-the-hole drill being provided as a part of drilling equipment also having a drill rod, the fuel tank comprising a largest rotation diameter in a transverse direction of a drill hole is at the most equal to a largest rotation diameter of the drill bit, whereby the fuel tank is insertable into the drill hole and that the fuel tank is provided at drilling equipment or in connection with drilling equipment.
 2. A fuel tank as claimed in claim 1, wherein the fuel tank is provided at the drill rod or in connection with the drill rod.
 3. A fuel tank as claimed in claim 1 wherein the fuel tank is provided at the down-the-hole drill or in connection with the down-the-hole drill.
 4. A fuel tank as claimed in claim 1, further comprising means for pressurizing the fuel tank.
 5. A fuel tank as claimed in claim 4, wherein the means for pressurizing the fuel tank comprise a flushing air channel.
 6. A fuel tank as claimed in claim 1, wherein the fuel tank is divided into at least a pressure space and a fuel space, which are separated from one another by an elastic, film-like material.
 7. A fuel tank as claimed in claim 1, wherein a volume of the fuel tank is such that it is possible to fit at least a fuel amount consumed by the down-the-hole drill during one work shift inside it.
 8. A method for feeding a fuel-operated down-the-hole drill having a drill bit with fuel, the method comprising the steps of: inserting the down-the-hole drill and a fuel tank, which is arranged at or in connection with drilling equipment, a largest rotation diameter of which in a transverse direction of a drill hole is at the most equal to a largest rotation diameter of the drill bit, into the drill hole; producing a pressure in the fuel tank for improving the fuel feeding and feeding fuel from the fuel tank to a motor of the down-the-hole drill.
 9. A method as claimed in claim 8, wherein pressure in the fuel tank is produced by a flushing air channel.
 10. A method as claimed in claim 8, wherein pressure in the fuel tank is produced by pre-pressurizing the fuel tank during a fill-up of the tank.
 11. An arrangement for feeding a fuel-operated down-the-hole drill having a drill bit with fuel, the arrangement comprising drilling equipment including a down-the-hole drill, a drill rod, a fuel tank, and means for feeding fuel from the fuel tank to the down-the-hole drill, wherein a largest rotation diameter of the fuel tank in the transverse direction of a drill hole is arranged to be at the most equal to a largest rotation diameter of the drill bit, whereby the fuel tank is insertable into the drill hole, and that the fuel tank is provided at or in connection with the drilling equipment.
 12. An arrangement as claimed in claim 11, further comprising at least one flushing air channel, the at least one flushing air channel being arranged to produce a pressure in the fuel tank.
 13. An arrangement as claimed in claim 11 or 12, wherein the fuel tank is provided at or in connection with the drill rod.
 14. A rock drilling rig comprising an arrangement for feeding a fuel-operated down-the-hole drill having a drill bit with fuel, the arrangement including drilling equipment having a down-the-hole drill a drill rod a fuel tank and means for feeding fuel from the fuel tank to the down-the-hole drill, wherein a largest rotation diameter of the fuel tank in the transverse direction of a drill hole is arranged to be at the most equal to a largest rotation diameter of the drill bit the fuel tank being insertable into the drill hole, and that the fuel tank is provided at or in connection with the drilling equipment. 